Programming in the Large Again

Good architecture frees us to choose the right tools and techniques, allowing us to adapt easily and concentrate on solving real problems rather than our made up ones. In this talk we will run through some stereotypical projects looking at the properties of good architectures and how these play into our ability to adopt better tools like Scala and FP. We will attempt to ground the magical architecture ponies, with real examples of my past projects where things have gone well and probably of more interest where they really have not.

This is a slightly improved version that I presented at NICTA on 28th of November 2013.

Transcript

1. PROGRAMMING
   in the
   LARGE
   Ģ
   B
   ģ
   z
   @markhibberd
   

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2. Ģ
   B
   ģ
   z
   SYSTEM
   FORMULATION
   

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3. How do we arrive at
   Systems?
   

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4. Modernization
   Old New
   

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5. Productionization
   Prototype Production
   

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6. Consolidation
   Bigger
   Small
   Small
   

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7. Modularization
   Big
   Smaller
   Smaller
   

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8. Greenfield
   Legacy
   

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9. Incremental
   Base
   More More
   

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10. THESE ARE NOT
    SYSTEMS
    

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11. Any organization that designs a
    system will produce a design whose
    structure is a copy of the organization's
    communication structure
    Conway’s Law
    

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12. The rules and boundaries
    of our systems should
    stem from architecture
    not organisation
    

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13. How the system interacts
    What is the systems purpose
    Macro Architecture
    Domain Architecture
    How the system is built
    Micro Architecture
    

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14. Systems as the unit of work
    Not unit of work as a system
    

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15. Ģ
    B
    ģ
    z
    SYSTEMS
    of
    SYSTEMS
    

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16. The thing about real systems is
    AUTONOMY
    

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17. CROSS LANGUAGE CODE SEARCH
    AS AN EXAMPLE
    

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18. Code search the JVM wrong way
    Pick Framework
    

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19. Scala + Play
    Pick Language + Framework
    Code search the JVM wrong way
    

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20. UI API
    FILESYSTEM
    Code search the JVM wrong way
    Scala + Play
    

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21. UI API
    DB INDEXER
    Code search the JVM wrong way
    Scala + Play
    

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22. SYSTEMS, NOT SUB-SYSTEMS
    

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23. Code search as Systems
    INDEXING SEARCH
    

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24. Code search as Systems
    Domain Architecture
    INDEXING SEARCH
    

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25. Code search as Systems
    INDEXING SEARCH
    CODE
    CTAGS
    CTAGS
    application/html
    application/search.v1+json
    

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26. Code search as Systems
    INDEXING SEARCH
    CODE
    CTAGS
    CTAGS
    application/html
    application/search.v1+json
    Macro Architecture
    

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27. STANDARD FORMATS HELP
    GIVE US AUTONOMY
    

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28. Code search as Systems
    INDEXING SEARCH
    Scala
    Embedded Server
    OS for logging
    Bourne Shell
    Exuberant CTAGS
    Deploy as git hook
    OS for logging
    OS for services
    

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29. Code search as Systems
    INDEXING SEARCH
    Micro Architecture
    Scala
    Embedded Server
    OS for services
    OS for logging
    Bourne Shell
    Exuberant CTAGS
    Deploy as git hook
    OS for logging
    

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30. Code search as Systems
    INDEXING SEARCH
    Micro Architecture
    Scala
    Embedded Server
    OS for services
    OS for logging
    Bourne Shell
    Exuberant CTAGS
    Deploy as git hook
    OS for logging
    MORE AUTONOMY
    

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31. RULES
    ARCHITECTURE IS ABOUT
    NOT BOXES
    

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32. Signs of failure
    Systems are not autonomous
    Systems share a domain model
    Systems need to be evolved in step
    Systems need to be built by single team
    Systems share a data base
    

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33. Systems as the unit of work
    If you can’t add a person to
    your project then you are
    failing worse than you think
    again
    An Aside
    

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34. Ģ
    B
    ģ
    z
    EVOLUTION
    

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35. Thinking ahead is not about avoiding change
    Thinking ahead is about letting us change at
    different rates for different problems
    

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36. Indexing V2
    INDEXING SEARCH
    Scala
    Embedded Server
    OS for logging
    Haskell
    Static Executable
    OS for services
    OS for logging
    OS for services
    

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37. INDEXING SEARCH
    Scala
    Embedded Server
    OS for logging
    Haskell
    Static Executable
    OS for services
    OS for logging
    OS for services
    Micro Architecture
    Indexing V2
    

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38. now vs later
    priorities shift over time,
    can't let early traction
    sacrifice long term speed
    An Aside
    

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39. INDEXING SEARCH
    Scala
    Embedded Server
    OS for logging
    Haskell
    Static Executable
    OS for services
    OS for logging
    OS for services
    Indexing V2
    DIFFERENT SYSTEMS SAME RULES
    DIFFERENT SYSTEMS DIFFERENT RULES
    An Aside
    

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40. Macro Architecture
    Indexing V3
    INDEXING SEARCH
    CODE
    CTAGS
    CTAGS
    application/html
    application/search.v1+json
    Super-Zippy Format
    

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41. Macro Architecture
    Search V2
    INDEXING SEARCH
    CODE
    CTAGS
    Super-Zippy Format
    application/html
    application/search.v1+json
    Super-Zippy Format
    

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42. Notice how easy it is to think of
    evolution in the large
    

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43. Rates of change
    domain
    macro
    micro
    

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44. Rates of change
    domain
    macro
    micro
    Freedom to choose tools and technology by succeeding at domain and protocols
    

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45. HOW DO SYSTEMS THINK
    HOW DO SYSTEMS COMMUNICATE
    HOW DO SYSTEMS CHANGE
    

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46. Implications at
    Scale
    

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47. The concept of micro-services are great
    An Aside
    The concept of small libraries are great
    But they are not enough without
    thinking in systems
    

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48. Larger Systems of Systems
    

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49. How long does it take to get 1 line
    of code to production
    

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50. Larger Systems of Systems
    

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51. Mistaking Modules For Systems
    

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52. Mistaking Modules For Systems
    

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53. Mistaking Modules For Systems
    

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54. Implication of Autonomy
    USERS
    

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55. Implication of (lack of) Autonomy
    USERS
    

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56. Ģ
    B
    ģ
    z
    SYSTEMS
    in
    ACTION
    

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57. CMSs hold customer data hostage
    CONTENT ANALYSIS & DATA MINING PROJECT
    Free data
    Analyse data
    Derive data
    CMSs tied to horrible platforms
    Goals
    Constraints
    

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58. CONTENT ANALYSIS & DATA MINING PROJECT
    Prototype Production
    1
    

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59. CONTENT ANALYSIS & DATA MINING PROJECT
    Prototype Production
    1
    JSP Java
    

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60. CONTENT ANALYSIS & DATA MINING PROJECT
    Prototype Production
    1
    1 JSP Java
    

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61. CONTENT ANALYSIS & DATA MINING PROJECT
    Prototype Production
    Smaller Smaller
    1
    2
    Java
    1 JSP
    

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62. CONTENT ANALYSIS & DATA MINING PROJECT
    Prototype Production
    Smaller Smaller
    1
    2
    1 JSP Java
    Java
    Scala
    

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63. WHAT I IMAGINED
    DATA
    WEB
    CORE LEECH PORTAL
    CONTENT ANALYSIS & DATA MINING PROJECT
    

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64. WEB / CORE / DATA / LEECH
    WEBSHERE
    REALITY SETTING IN
    

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65. CAUGHT THINKING IN THE
    SMALL
    MODULES - LIBRARIES - TECH
    

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66. We should leverage architecture changes
    rather than force new technology
    

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67. CONTENT
    ANALYSIS
    IDENTITY
    CONTENT
    STORE
    QUERY
    ENGINE
    A Better Approach
    

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68. Play 1.1 App
    Our Starting Point
    

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69. Play 1.1 App
    Enabling Moves
    IDENTITY
    

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70. Play 1.1 App
    Protobufs
    Thrift
    HTTP
    Establishing Rules & Autonomy
    sbt-assembly
    OS package
    Containers
    IDENTITY
    Protocols
    Deployment
    

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71. Play 1.1 App
    Identifying Demand
    CONTENT
    STORE
    IDENTITY
    

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72. Play 1.1 App
    Validation
    CONTENT
    STORE
    IDENTITY
    

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73. Play 1.1 App
    Repeat
    CONTENT
    STORE
    IDENTITY
    CONTENT
    ANALYSIS
    

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74. Repeat
    CONTENT
    STORE
    IDENTITY
    CONTENT
    ANALYSIS
    QUERY
    ENGINE
    

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75. architecture is an everyday task
    

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76. good architecture means never
    having to rewrite
    

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77. All editors are bad, really bad
    ONLINE CONTENT EDITING
    Something aaS
    APIs
    Ready to change
    Small team, tight deadline
    Goals
    Constraints
    Lots of ideas, not sure what would work
    

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78. Spelling Identity Templates
    Editor
    Customer
    UI
    Domain Architecture
    

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79. Spelling Identity Templates
    Editor
    Customer
    UI
    Macro Architecture
    HTTP / JSON
    

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80. C Scala Scala
    Spelling Identity Templates
    Editor
    Customer
    UI
    Micro Architecture
    Scala/JS Scala
    Postgres
    Postgres Postgres
    syslog
    jail per service
    rc.d
    1 executable
    Minimal stack
    

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81. Editor was working well
    ONLINE CONTENT EDITING
    Incremental
    Multiple Versions
    Add not modify
    Needed to add more services
    Goals
    Constraints
    System need to keep running
    

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82. Spelling Identity Templates Content
    Editor Analysis
    Customer
    UI
    

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83. Spelling Identity Templates Content
    Editor Analysis
    Customer
    UI
    HTTP / JSON
    

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84. Spelling Identity Templates Content
    Editor Analysis
    Customer
    UI
    Scala/JS Scala JS
    C Scala Scala Scala
    multilog
    jail per service
    daemon tools
    1 executable
    Minimal stack
    

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85. Demand for standalone features
    ONLINE CONTENT EDITING
    Quick
    Minimal Overhead
    Maximum Reuse
    Not tied to our editor
    Goals
    Constraints
    Run in parallel to current system
    

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86. Spelling Identity Templates Content
    Editor Analysis
    Customer
    UI
    

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87. UGLY BITS
    

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88. Spelling Identity Templates Content
    Editor Analysis
    Customer
    UI
    Glue
    Glue Glue Glue
    Glue
    Glue
    Glue
    

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89. Spelling Identity Templates Content
    Editor Analysis
    Customer
    UI
    Config
    

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90. ARCHITECTURE SHOULD HAVE
    RULES FOR HOW WE SHARE CODE
    

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91. Ģ
    B
    ģ
    z
    RECAP
    

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92. RULES
    ARCHITECTURE IS ABOUT
    NOT BOXES
    

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93. good architecture means never
    having to rewrite
    

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94. Thinking ahead is not about avoiding change
    Thinking ahead is about letting us change at
    different rates for different problems
    

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95. Systems as the unit of work
    Not unit of work as a system
    

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96. The thing about real systems is
    AUTONOMY
    

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97. Ģ
    B
    ģ
    z
    FIN
    @markhibberd
    

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98. References + More Info
    Stefan Tilkov's Breaking the Monolith slides video
    Coda Hale and Ryan Kennedy on "Streamie" notification service at yammer
    Slide Deck v2
    v1
    

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